can't install itunes 4.9!

hey all!
i need some help installing itunes. at the moment i have itunes 4.7.1. do i need to update to 4.8 to update to 4.9? When i use Installer it says that i have "a newer version of the package is all ready installed". I know its not, but i did a search for itunes in finder and i didn't find anything anyway. Please heklp and i hope my problem is clear.

I am not near my System at this time and I don't recall were the receipt folder is located. I think it is in the Library folder. In that folder locate the itunes document/file and delete it. Once that is done, you should be able to use the software update to install the latest version of itunes. The receipt folder is used to keep track of what software and the version that is loaded on your system.

Life isn't about waiting for the storm to pass, It's about learning to dance in the rain!

i imagine thats where the problem lays, i did try to update in software update, but it appeared as another application in my application home folder and when i opened it it would only stay open for a few seconds and then close, that is why i am trying to download it all together.